


Scale and Steel

by Gaqalesqua



Category: Fallout (Video Games), Fallout 4
Genre: Anal Fingering, Anal Sex, Biting, Blow Jobs, Cunnilingus, F/M, Kissing, Loss of Virginity, M/M, Masturbation, MerMay, MerMay 2019, Oral Sex, Strength Kink, Teasing, Threesome, Threesome - F/M/M, Wet Dream
Language: English
Status: Completed
Published: 2019-05-04
Updated: 2019-05-31
Packaged: 2020-02-25 22:09:31
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 5
Words: 17,193
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/18710647
Author URL: https://archiveofourown.org/users/Gaqalesqua/pseuds/Gaqalesqua
Summary: Arthur has never put much stock in the supernatural. Not until missions along the sea start going better than they should.





	1. Chapter 1

Arthur rubbed his eyes, staring down at the reports that lined the desk in front of him. He’d gone over them three times now, each time adding more notes and underlining more sections in pencil, as though it would suddenly all fall into place. He’d been warned that the Commonwealth was different to the Capital. That things were more ruined, more abandoned. That the Institute were responsible for all manner of troubles that would come his way.

Except that he doubted the Institute was behind a series of unforgettably successful missions up and down the coastline.

Four files were open, their names printed in thick black letters. He scanned them again. It just didn’t make sense.

**MISSION: SPECTACLE ISLAND**

**CASUALTIES: 0**

**SHOTS FIRED: 0**

**HOSTILES: 0**

**MISSION STATUS: SUCCESS**

Danse had included a line in the report that simply said _Mirelurk nests empty. No Mirelurks in location. Sonar beacon was non-functioning._

Nahant had been the same. The _Northern Star_ had been different, if only because the original crew, all ghouls, had put up a fight, but once again, empty Mirelurk nests had dotted the sand below the wreck. And Salem…

_Deployed soldiers confirm music coming from the beach as they approached the town. Minimal contact with hostiles. All Mirelurks retreated to the water and had fully evacuated the town by the time of occupation. Single survivor of the settlement was rescued from the roof of dwelling. Held watch overnight to confirm successful capture of settlement. Night watches were Towers and Hendy, both confirmed singing coming from the sea and no Mirelurks along the shore. Voice was female. Attempted contact with singer in case of stranded Wastelander. Singer did not respond. Singing ended at 0400 hours. Towers reports single splash 100 metres from shoreline. No body recovered._

Surely no sane woman would be out on the ocean at night, risking the Mirelurks, just to _sing_. He frowned. Some of the reports about Dunwich Borers had mentioned the raiders there being mad, but there was madness, and there was singing on a Mirelurk-infested coastline. And then there was the matter of the Mirelurks disappearing into the sea, chasing the song. He could have rationalised that as them chasing their prey, but the reports hadn’t mentioned screaming. As Danse had said, there hadn’t been a body to recover. And Arthur had seen his fair share of Mirelurk victims in his life.

He needed a drink. Or some coffee. Something. He’d been poring over this for hours. Besides, Danse was due to be back from the mission to Fort Strong soon. Arthur closed up the files, his mind still whirring. A woman who had lured the Mirelurks out of Salem and saved his men from a fight was someone he wanted to meet. Maybe she lived on a boat out in the ocean? It was unlikely she could have missed the Vertibirds heading up to Salem if she lived on the sea, after all, and perhaps she’d thought to save them a battle by luring the ‘Lurks out before his soldiers had arrived.

There _was_ something in the back of his mind that had strung a few facts together, but Arthur knew that was _nonsense_. It couldn’t be true. Radiation might have burned the world around him, but that didn’t mean that the supernatural was suddenly real.

He was halfway back from the mess, coffee in hand, when Danse’s group returned from Fort Strong. Two Knights carried another on a stretcher. Arthur immediately looked for blood. There was none, and when the Paladin appeared at the back of the group, he approached him.

“Report, Paladin,” he began, and took a drink of his coffee.

“Mission successful,” Danse replied. His eyes darted to the stretcher. “But…something happened again.”

Arthur frowned. “Again?”

“Again,” Danse agreed. “It’s easier if we show you.”

Nodding, Arthur followed Danse down the hallway, and when they reached the infirmary, the Knights inside had already helped their patient onto a gurney. The man was naked, wrapped in a white sheet, and his hair was soaked. He smelt _salty_.

Arthur’s brows furrowed. “What happened?”

“Bristow fell out of a vertibird,” Danse told him. “Damaged one of his suit legs and part of his helmet when he hit the water. He almost drowned.”

“Almost?” Arthur looked back at the shivering Knight.

“S-something,” the man’s lips were blue, his eyes wide and surprised, “p-pulled me a-out, E-elder.”

“We’re not sure what happened,” one of the others piped up. She shot a brief look at Bristow. “We did a full sweep of the water when he fell but we couldn’t see him. Radioed the airport to request a search and rescue team, but…well…”

The other Knight cleared her throat. “We were patrolling the beach when this huge wave crashed onto the sand, and the next thing we knew, Bristow was lying on the sand, coughing up his lungs, sir.”

“Did you see anyone with him?” Arthur asked.

She shook her head. “No sir.” Then she paused, squinting. “Well…I’m not sure. Nobody washed up with him, but…I think, in the wave…”

“In the wave?”

“There was something, sir. Something that looked…sort of golden-orange.”

Arthur frowned. “Golden orange.”

“Like scales, sir.”

“Scales.” That string of facts in the back of his mind came to the forefront. “Knight, did you hear any music?”

“No music, sir.”

Arthur paused, then nodded. “Bristow, you’re confined to the medical bay until Cade can clear you for duty. We’ll have your suit retrieved from the bay.”

“Thank you, sir.”

“As you were.”

 

* * *

  

Arthur knew he was thinking about it too much.

He knew he was thinking about it too much because he was hearing things. He had to be. There was no way there was _actually_ music wafting beneath his door. He was focusing too hard on this idea of a woman with golden orange scales who could lure out Mirelurks with her voice.

He knew what a mermaid was. And there were some things he found impossible to believe in.

The music was still coming from under his door.

He tried to think of something else. Vertibird engines. The hiss of hydraulics. Nothing human or organic. It didn’t work. The sound was filling his room, beautiful and haunting. It made him twitchy. He wanted to rip off his covers and run to find its source but he grabbed hold of his mattress until his knuckles turned white, and held himself there like an anchor.

The sound seemed to go on. Maybe for hours. Maybe for minutes. He didn’t know. He was almost paralysed now. The energy from earlier had gone. His eyes felt heavy. He kept clutching the mattress, hoping he wouldn’t find himself walking out to the forecastle. The last Maxson, dead from falling off the Prydwen because he heard a beautiful voice.

And then it was over. Or maybe he’d fallen asleep. He came to, still lying in bed, body feeling invigorated. Blinking, Arthur realised that he might have just had the best sleep of his life.

And that was exactly what Danse said when they met in the mess hall. Fresh Mirelurk omelette, courtesy of the empty nests and leftover eggs, paired with razorgrain bread and Brahmin butter, awaited them along with silt bean coffee, and they took their seats.

“I would’ve thought you’d have been up all night, thinking over those reports,” Danse began, sprinkling a little salt on his eggs. “Or maybe you sleep better when your brain is working that hard.”

Arthur spread the butter on his bread. “I should be exhausted,” he admitted. “Spent all night wondering what exactly we’re dealing with here. And then,” he paused, knife and fork in hand, “then I heard…I don’t know. Music.”

Danse’s brow furrowed. “Music?”

“A song,” Arthur said. “A woman, singing.”

“Definitely over-thinking this,” Danse told him. “I didn’t hear anything all night. What time was it?”

Arthur took a long drink of coffee. “I don’t know,” he sighed. “All I can remember is being completely…” He looked down at his breakfast. “It was the most beautiful thing I’d ever heard.”

“Huh.” Danse’s brows were still drawn, and he looked back at his breakfast. “Just you heard it?” Arthur nodded. Danse hummed. “I don’t like the thought of that. You think it’s a trap?”

Arthur didn’t reply for a while, taking a moment to eat some of his breakfast. “It could be. I felt… _drawn_ to the sound too, like it was calling me. I think I almost went to it.”

“I don’t like that at all,” the Paladin muttered.

Arthur chewed slowly. “Do you think I’ll hear it again?”

“Undoubtedly,” Danse sighed. “What worries me is that only _you_ are the one who _can_.” He stirred his coffee. “Do you think it was close by?”

“No.” Arthur shook his head. “It seemed to be coming from further away.”

Danse probed his teeth with his tongue, going silent. “The only thing I can think of is staying overnight in your quarters, on the couch. If I don’t hear it, but you do, then we may have problems.”

“You have another mission tomorrow,” Arthur reminded him. “Taking down Libertalia.”

“If I end up as invigorated as you are, I doubt that’ll be a problem,” Danse muttered. He looked up at Arthur. “What do you think it is? Realistically.”

Arthur sighed. “Realistically? I’m going mad. Unrealistically…” He put down his fork. “Do you believe in the supernatural?”

Danse’s brows rose. “What are you saying?”

“I assume you’ve heard of mermaids.”

“Now you’re definitely going mad.”

Arthur ran a hand through his hair. “Maybe. Maybe not. We’ll find out later.”

 

* * *

  

Arthur kept an eye on the time as he sat down on the couch with Danse. The Paladin was sitting with his rifle slung over his lap, and Arthur had brought his own gun in case of emergencies. He buried the urge to bounce his leg as he waited. He had no idea when the singing had started, but it was almost midnight now, and though he felt a slight drag on his eyelids, he wasn’t as tired as he should have been.

“So, would you rather I heard it, or I didn’t hear it?” Danse asked him quietly.

“I don’t know,” Arthur admitted. “I truly don’t. If you don’t hear it, then we both know I’m going mad.”

“Who’s next in the line of command?” Danse wondered. “Or are you going to fist-fight whoever will take over from you?”

“You know we stopped those traditions years ago,” Arthur muttered.

His screen flashed briefly with a _00:00_.

And the song started again.

His skin prickled. That twitchy energy surged through him again, feeling like heat. “Danse,” he whispered. “Tell me you can hear that.”

The Paladin squinted. One hand cupped his ear. He paused as they stayed as quiet as they could. Danse kept listening. “No,” he murmured.

Arthur almost forced himself to stay seated. He needed to go to that sound. Needed to follow it. “Danse.” It was worse than last night. “Danse, stop me from doing anything stupid.” And then he tore himself from the couch and stood on shaky legs. “Stop me if I try to jump.”

Danse jumped to his feet, still holding his rifle. “You’re not going outside,” he whispered. “Arthur!”

“I need to know!”

He forced his steps to be measured, to look like he was going for a leisurely stroll instead running outside to listen. Danse followed. He didn’t try to stop him and Arthur could still feel that antsy energy coursing through his veins. It was like spine-tingling warmth. And when he finally got to the door that lead to the forecastle and threw it open, even the cold wind couldn’t dampen the heat.

The song was louder. It seemed to echo up from below him. But from behind, on the beaches around the airport. He was on the wrong side. He needed to be on the flight deck.

It was almost painful to pull himself back indoors, but he grabbed the most powerful scope he could find on his way. Danse was still following him, following orders. He hadn’t tried to stop him yet. Arthur hoped that was because he hadn’t done anything crazy.

“Arthur,” he hissed. “Arthur, this is insane.”

“I need to know I’m not _going_ insane, Danse!” Arthur hissed back.

“What are you planning on doing, anyway?”

They piped down as they made their way past the command deck, so as not to disturb the Lancers. This was a perfectly normal midnight walk.

Even if Danse was carrying a rifle.

“Just looking,” Arthur promised. “I need to see.”

The wind battered them as they got to the flight deck, but Arthur ignored it, marching straight up to the rails on the other side. He took a look through the scope, sweeping his gaze over the beaches. The song seemed to tug his hands, dragging his sight southward.

He almost dropped the thing when he saw the figure draped across some rocks, shimmering in the moonlight. He couldn’t make out any colours thanks to the monochrome scope, but they were dark-skinned, feminine, with long dark hair that tumbled around her shoulders.

“Danse,” Arthur whispered. He handed him the scope, and pointed down. “Look.”

He knew when Danse had spotted her because the Paladin gasped, and slowly put down the scope.  Thanks to the lights around them, he could see the perfect expression of shock on Danse’s face.

“Well,” Danse finally whispered, “I don’t think you’re mad.”

Arthur took the scope back, and focused on her again. “But you still can’t hear her.”

Danse shook his head. “I can see that she’s singing, though.”

Arthur heard the song change. That sleepiness washed over him again. “She’s…the music is different. I need to sleep.”

“She’s singing you to sleep?” Danse murmured. “No wonder you woke up so refreshed.”

Arthur rubbed his eyes. “What should I do tomorrow?”

“We still don’t know what she wants,” Danse warned. “We shouldn’t be reckless about this.”

Arthur nodded, slipping the scope into his pocket. Danse was right. He needed to be cautious.


	2. Chapter 2

“This is _not_ being cautious!” Danse hissed, peeking out from behind the crumpled plane wing.

“Then I suggest you head back and tell Kells to stop me,” Arthur muttered, holding up a hand. “It’s almost midnight.”

“How do we know we weren’t both hallucinating?” Danse added, keeping his voice low.

“And saw exactly the same thing?” Arthur retorted, craning to listen to the sound of the ocean. “We weren’t drinking. It’s not possible.”

“But supernatural creatures that sing songs to lure away Mirelurks? That’s perfectly rational,” Danse muttered.

“We’re squatting behind a piece of wrecked airplane, at almost midnight, waiting to see a mermaid. _None_ of this is rational,” Arthur replied.

There was a splash.

A long pause.

A soft humming filled the air. Arthur stifled a groan as it seemed to thrum through him, practically dragging on him like pairs of hands that grabbed his wrists and tried to tug him towards the sound.

Someone tapped on his shoulder. Danse. He turned around to see the Paladin watching him, his face drawn in concern. He held up a thumb, butterflies exploding in his stomach.

The voice grew louder. Arthur pulled the headlamp out of his pocket, and stood. It was almost a relief to do so. Like a reward for doing what he was meant to. He gave himself a few moments to try and compose himself, taking long, deep breaths.

And suddenly the song stopped.

The tugging sensation stopped too, and Arthur steeled himself, pushing away from the broken wing. The moonlight was bright above them, but he didn’t want to chance relying on it. He and Danse both had flare guns too.

Just in case.

There was a long, loud, _feminine_ sigh from the other side of the wing. Arthur gasped, taking a few steps forward. Rounding the debris, his eyes met the water, then the rocks, and then-

Her scales weren’t golden.

Arthur switched on the lamp.

Even in the bright yellow of the light, the glimmering tail that she draped down from the rocks couldn’t be mistaken for anything other than a vibrant blue. His eyes followed upwards, to a pair of hands placed delicately in her lap. He tried not to stare as he realised that there was no real separation of woman and fish. The scales simply faded around her lower hips, replaced by blue fish skin that gave way to a human body, dark and gleaming wet with recent seawater. He followed the smooth curves upwards.

Arthur had seen women naked. He was Brotherhood. They lived on a blimp. He couldn’t _avoid_ the naked body sometimes. And every soldier in the Brotherhood had a similar body – compact, suited for combat, with little excess flesh.

The mermaid in front of him had her hair draped across her chest, but he’d already seen the softness in her belly, and when his eyes kept moving upwards, the unmistakeably full curves, hidden partially behind the dark locks, were something he’d really only seen in whatever pinup mags made it into Brotherhood circles.

He noted, briefly, that her arms were dappled with fish skin and scales on the outsides, over her shoulders and around her elbows, down to her forearm.

He finally met her gaze.

Bright blue eyes gazed back at him, from beneath a few thick wet strands of dark hair that had fallen over her face, and she pushed them back. She looked young. Not much older than he did. He resisted the urge to rub his face, suddenly self-conscious of the wear and tear on his skin when compared to the smooth softness hers seemed to have.

Her hair was woven with shells, and it seemed to spill down her back. It was almost a relief to tear himself briefly from her eyes.

“I didn’t realise you could walk on the ground without one of those strange suits of armour,” the mermaid said softly. “I thought maybe you were a different kind of human.”

Arthur felt his face burn when his cock throbbed in response.

“A…different kind?” he repeated.

She smiled. “There are plenty of you that can walk on the ground, you see,” she began. She sounded like she was humouring him. “But when you all kept dropping out of that…” she pointed up at the Prydwen, “ _aircraft_ , is that what it’s called?”

“Yes.” His voice cracked. He coughed. “Yes, it’s…it’s a blimp. It’s called the Prydwen.”

“Prydwen,” she repeated. “It’s beautiful. Fascinating. But I thought that you might be different to the humans of the Commonwealth. That you could all fly. The humans before the war used to drive around in large machines, after all, even though they could walk perfectly easily, so my logical conclusion was that flying humans might need the same sort of transport.” Her eyes flicked briefly up and down his body. He straightened up, and she laughed. “I see you can walk perfectly on the ground without needing armour, though.”

His mind ran with a million questions that never made it out of his mouth. Who was she? Why was she helping them? _Was_ she helping them? How did she understand him? How did _he_ understand _her_? He could believe in mermaids with ease now – that didn’t explain how and why one was sitting in front of him, naked, watching him like he was an unexpectedly delightful addition to her day.

“You’re real,” was what finally stumbled out of his mouth.

That earned him another laugh, her voice soft and husky. She nodded. “I’m real,” she agreed.

“I thought I was going mad,” he added. “Seeing things. Hearing things.”

She held out her arm, smiling. “Do you want to check?”

“Arthur!” Danse hissed from his cover.

The mermaid drew her arm back, gazing over at the Paladin. “I wondered when you were going to appear.”

Arthur’s brows rose. “You knew we were both there?”

She tucked some hair behind her ear. “I heard you talking.”

Danse coughed. “I wasn’t going to let him go chasing a…a _fairytale_ without keeping an eye on him. He’s important to the Brotherhood.”

“He certainly seems to be,” the mermaid agreed. “Your forces keep pledging themselves to _Elder Maxson_ whenever they charge into battle.”

Arthur frowned. “How do you know my name?”

“You heard my song, right?” she asked.

He folded his arms. “What’s that got to do with it?”

“It’s magical, in case you hadn’t realised.” She leaned forward. Some of her hair dropped into her lap and Arthur kept his eyes firmly on hers. “I kept hearing it yelled during fights and I wondered just what kind of person would inspire that loyalty. So I wove a song of finding with your name in mind.” She gestured briefly to Danse. “Also, he called you Arthur just now.”

“So you’re curious?” Arthur asked. “Is that why you’ve been…have you been driving away the Mirelurks?”

“That’s me,” she agreed. “Your blimp keeps casting shadows in the ocean, so I decided to investigate. And, well…” She shrugged. “I’ve never seen anything like it in my life. So many people. So much noise. Even the Castle wasn’t this lively back in its day.”

“The Castle?” Danse repeated. “The Minutemen’s stronghold?”

She nodded. “I tried my best to help them. Unfortunately, there are times when I need to sleep, and Mirelurk Queens…well, they take more effort than a few songs to deter.”

“A Queen,” Danse murmured. “Fuck. That must have rolled over them without breaking a sweat.”

The mermaid sighed. “Indeed.”

“And I assume you’re the reason why nothing has been lurking on this beach?” Arthur guessed.

She smiled. “You assume correctly.”

He paused. This was going…too well. Too easy. There were far too many forces at work in the Commonwealth that wanted to harm instead of help, and just because this supposed force for good was beautiful, that didn’t mean he could be any less suspicious.

“You’re really doing this just to help?” he asked.

A small, slightly embarrassed smile crept onto her lips. “Well,” she chuckled, “I’ve…I’ve always been _fascinated_ by humans. But…well, most in the Commonwealth live inland, and no mermaid is stupid enough to venture into the rivers. I’ve heard enough horror stories about my people being stolen from the water.” Another pause. “Besides, that strange man in Salem thought I was a Mirelurk and tried to shoot me.”

“In fairness, he was more than likely hallucinating from lack of sleep,” Danse muttered.

“Inland folk don’t tend to know what I am anyway,” she added, shrugging. “Which…is probably why that man thought I was a Mirelurk. And before the bombs fell, the coast was just _full_ of people. It was too dangerous to do more than just watch from afar.”

Arthur started. “Wait, did you say _before the bombs fell_?” he asked.

She nodded. “I used to watch the lights come on at night and see if anyone was wandering along the beach. It was beautiful.”

“You…” Arthur swallowed. “You were…alive before the bombs?”

“Well, yes.” She raised her hands and shrugged. “It wasn’t that long ago.”

“It was two centuries,” Danse managed. “The only other people to survive that long are all ghouls.”

“I know two centuries seems like a long time, but really, it isn’t,” she protested. “As my people go, I’m not particularly old _or_ young.”

“…how old _are_ you?”

Arthur managed to slow the words down to stop himself from tripping over them.

“Well,” she paused to think, “I was born in your human year of 2048.”

Danse’s strangled gasp filled the air behind him.

“240,” Arthur breathed. “You’re 240 years old.”

She nodded. “Well, yes. But as I said, that’s paltry. I know merpeople who were alive when you were still riding _horses_.” A pause. “I know merpeople who were alive before the Castle existed.”

Silently, Arthur was thankful that Quinlan wasn’t here. He would have been requesting a mile of unused holotapes and the rest of his life to speak to this woman. Merwoman.

“I don’t know your name,” he suddenly realised.

She let out an embarrassed laugh, hand over her mouth. “I’m sorry, I got so carried away, I completely forgot to introduce myself. I’m Roshanara.” She held out her hand. “Is this still how you greet people?”

Arthur swallowed down his excitement and accepted the handshake. Her palms were rough, her grip firm and unusually strong.

“Roshanara,” he repeated.

“And what would you like to be called?” she asked. “Arthur? Elder Maxson?”

 _Arthur, just Arthur_ , he wanted to say. “Arthur,” he agreed, trying to curb his excitement. “I’m Arthur.”

Roshanara glanced over his shoulder to the Paladin lurking by the plane wing. “And you?” she called.

“Paladin Danse,” Danse replied.

“Paladin Danse.” She still hadn’t taken her hand from Arthur’s. “Arthur Maxson. A pleasure to meet you both.”

Arthur nodded. “What now?”

Her fingers tucked beneath the cuff of his coat and stroked over his pulse. “Maybe you should sleep. It’s dark, after all, and what little I know of armies involves resting. And I know humans sleep at night. I’ve…well. My curiosity is sated, for now.”

“Will you be here tomorrow?” Arthur asked, returning the gesture.

She smiled. “Would you like me to be?”

“Yes.”

“Arthur,” Danse muttered.

“Then I’ll see you tomorrow night,” Roshanara said.

A deep, melodic voice echoed across the water. Arthur gritted his teeth. Just like Roshanara’s, it rushed through his body, leaving heat in its wake, and he quickly relaxed his jaw in case it gave her the wrong impression.

Not that she was looking. She quickly shifted on her rock, staring back at the dark, open water behind her. “I should go,” she said. “Thank you for meeting me, Arthur. And Danse.”

“Yes,” Arthur said, unsure what else to say. “And you.”

She smiled, and with that, she leapt off the rock. Her tail glittered in the moonlight, and then the sea swallowed her up. A fleck of salt water splashed onto Arthur’s cheek like a cold kiss.

“Holy shit,” Danse muttered behind him. “Holy _shit_.”

“That was a mermaid,” Arthur whispered. “A 240-year-old merwoman who has been chasing off Mirelurks to help _us_.”

“It’s crazy.” Danse moved to stand next to him. “We’re both high. We must be.”

Arthur wiped the water off his face. “Would that be easier to explain or not?”

Danse paused. “None of this is _easy to explain_ ,” he finally pointed out.

“That,” Arthur murmured, “is _very_ true.”


	3. Chapter 3

Well, she was there again.

Arthur hadn’t had anything alcoholic, he never touched drugs. Yet there she was, sitting up on that rock and smiling at him expectantly.

“Good evening,” she called, her eyes following his approach. “Did you sleep well?”

“How do you do that?” he asked, stopping at the waterline. “How do you make me sleep that deeply?”

She shrugged, her palms upturned. Arthur quickly forced his gaze back up to her eyes from where he had found himself lingering on the slope of her neck.

“I’m not sure. It just happens. I think about what I want to happen and it does.” She tilted her head. “Are you…cross?”

“No. Not at all,” he managed. “It’s…just. Fascinating.”

A soft laugh escaped her. “Thank you. I…I’m glad you think that. I don’t think I’m that interesting.” She flicked her tail and Arthur briefly saw the light glimmering off her scales. “What about you? Elder Arthur Maxson…everyone here follows you like you’re some kind of _king_.”

He snorted. “I lead the Brotherhood. They aren’t my subjects. They fight because we share ideals.”

Something in her expression opened up, like a new kind of interest. She leaned forward. That long hair swung gently aside.

“It’s been a while since I’ve seen people all band together under the same banner,” she admitted. “The Commonwealth hasn’t been the same since the Castle was taken.”

“Have you ever shown yourself to a Minuteman?” he asked.

“Once.” She paused. “Not long ago, a group of them tried to retake the Castle. I tried my best to help them, but…”

Arthur watched her eyes drop. She sighed. The sound cut through him and he recoiled, surprise rushing through him. Her sadness was obvious and it made his stomach churn. It felt like more than just empathy and he frowned. Was it wrong to be suspicious? He barely knew her. And yet he was drawn to her. He knew she could manipulate anyone using her voice and he hated the thought that she was intentionally weaving some spell around him to…

What? He didn’t know. He clasped his hands behind his back.

“Are you all right?”

He looked up, swallowing.  “Why did you want to meet me, really?”

Her brow furrowed. “Humans fascinate me. They always have. Is something wrong?”

Arthur tried not to look at her eyes but he felt his face burn as his gaze briefly dropped. He managed to focus on a patch of moonlit water behind her. “You said your voice was magical,” he pointed out.

She nodded. “You’re afraid I’m using it to cast a spell on you?”

He shrugged. “Wouldn’t you?”

A tiny smile tugged at her lips. “I…like the sound of your voice whether it’s magical or not. I can’t answer that one any other way.”

Arthur felt the tips of his ears burn. He almost wished he’d brought Danse so he’d have a reason to retreat. But he hadn’t. “You like hearing me talk?” he repeated. The churning in his stomach had died away, just a little.

Her eyes met his. “I think maybe we have a mutual appreciation in that sense.”

Well. He didn’t quite know what to say to that.

She tucked some hair behind her ear. “I’m not going to hurt you. I can prove it.”

His brows raised. “How so?”

With a grunt, Roshanara turned around and dropped back into the sea with a splash. Arthur drew back. Was that her proof?

The water nearby swelled and bubbled, glowing. Arthur froze, eyes widening as he watched a dark head breaching the surface. Then the mermaid was crawling out of the ocean, only without her tail. Gleaming scales now clung to her bare legs as she sat up, and pushed herself to her feet. Her legs trembled. Arthur darted forward without thinking, and Roshanara fell into his arms.

Water was soaking the front of his suit when he realised that she was still naked.

He froze again, his arms locking around her even as she grabbed him for support. She was warm. She smelt of salt and sand, and her hair seemed to be drying even as he watched it. Not that he was looking. His eyes were fixed on her face, because his cheeks were burning and he didn’t want to look down. His heart was suddenly pounding loudly in his chest.

There was a soaking wet, naked mermaid in his arms, and it looked like neither of them had expected to get here because Roshanara’s lips were parted, her eyes wide, and he could _feel_ her shaky breaths as she pressed against him.

Arthur wasn’t sure what to say. He’d been in a lot of different situations in his life, but nothing had ever prepared him for the reality of the softness leaning against him, or her heat, or her smell. She swallowed, looking down, and when his eyes followed her, he caught a glimpse of the curve of her breast, mostly hidden by his own body.

He took a step back, hoping she wouldn’t feel his erection pressing against her.

That didn’t work.

She’d been using him as a crutch. As he stepped back, she toppled forward, and this time, Arthur hadn’t braced himself. Stumbling, his heels scuffed against the sand. His foot slid on the wet ground.

They fell.

When she landed on him, her full weight was enough to wind him. Far from keeping her away from his lap, her hip pressed against the outline of his cock through his suit. Arthur’s face burned. He abruptly realised that she was _far_ heavier than he’d expected, and that beneath the softness, her muscles felt like steel cord.

He quickly looked away as she shifted, until she cleared her throat. Her brow was raised when he looked back at her.

“Are you going to let me go?” she asked. He didn’t trust himself to speak. Her voice was enviably even for this situation. He quickly released her, keeping his hands up by his head, and turned aside once more to let her move. He felt her thighs slide either side of his waist and his cock twitched expectantly. If he looked, would there be a patch of hair between her legs like a human woman? Would she look any different?

Roshanara to her feet, still a little shaky. “Here, I can prove I won’t hurt you,” she began. Arthur sat up, and watched as she reached out and touched the scrap of broken plane. Her hand squeezed at the metal.

It bent beneath her fingers.

His cock throbbed again.

“If you’re worried about my voice, using wax to block your ears will stop it,” she told him. “I can barely use this body. I just wanted to meet you.”

Arthur quickly got to his feet. Her hair was much shorter, and it still fell over her chest, covering her. He kept his eyes on her face, despite his gnawing curiosity.

“I can’t be that interesting,” he finally said.

She fidgeted, holding the plane for support. “I’ve never met a human before. Maybe I was weaving a spell without knowing it. My people are immune to it, so I’ve never had to learn to control it around humans. Whenever I used it, I did it on purpose.”

He put his hands behind his back because he didn’t know what else to do with them. “Like with the Mirelurks.”

She nodded. A small smile crossed her lips. “Like with the Mirelurks.”

She was dangerous. She didn’t know how to control her own powers. And she was _strong_. His rational side told him to run, do as she’d advised and stop her voice from reaching him.

“Are you afraid of me?” she asked.

Arthur paused. A good question. One he should have asked himself first. “I think you’re dangerous,” he finally replied. “Your abilities are dangerous. You don’t know how to control your own voice.” Her voice, which hadn’t had an effect on him since she’d used a human form. “And you’re strong enough to kill me with ease.”

She tapped her fingers against the metal. “I didn’t see it that way. I’m sorry. I just…got so excited at the thought of meeting a human.”

Arthur pulled his coat together, hiding his erection. He didn’t need to be thinking about that right now. He felt a little sympathy for her. And without her true form, her magic wasn’t there to help her emotions shape his. He looked at her. Now that her abilities were nullified, however briefly, his mind was a little clearer. And he knew the truth was, it didn’t matter.

This was a 240-year-old merwoman, who had probably risked her life to chase Mirelurks away to keep his men from a fight and had given him two full nights of fulfilling rest, for the first time in a long time.

Unless she was a synth.

Arthur looked at her, long and hard, remembering the way she had disappeared and reappeared without her tail. That paranoia itched at him and he took a few deep breaths. If she _was_ a synth, she would deny all knowledge.

“What’s wrong now?” she asked.

He folded his arms. “What do you know about the Institute?”

She _hissed_. Arthur’s eyes widened briefly.

“I can _smell_ what they’ve done in the water,” she growled. “When the Super Mutants came we didn’t know what they were or how they got out, but the first ones that came…they smelt _sterile_. I’ve killed more than enough that have been wandering up and down the coast. They’ve caught a few of us before, did you know that? When they first appeared. Whatever they do to humans, _no one_ deserves that. No one. It’s horrifying.”

He blinked. He hadn’t expected that. “You oppose them?”

“I oppose the way they pervert humans. That they haven’t gotten hold of one of my kind is only thanks to our caution.” She gazed steadily at him. “I know what they do to your people. They steal them away and leave something in their place. A synth. Is that correct?”

He paused. Then nodded. “They’re the reason we came to the Commonwealth in the first place. To drive them out and destroy them.”

A pleased, vicious look crossed her face. “Good. I’ll do what I can to help.”

Heat rushed through his face, down his body. It felt like…

It felt like she looked. Angry and pleased at the same time. He swallowed. The hardness at his thigh hadn’t gone away.

Wait.

“You can smell them?” he asked.

“Yes. Where the river meets the sea. It reeks of them. Everything in the Commonwealth has a smell. The Institute can be anything from sterile water, stale air or faint traces of chemicals. Super mutants…” Her lip curled. “They smell of blood and dirt and the kind of sweat humans create when they’re afraid. It’s awful.”

His breath caught. “Can you help me find them?”

Her brows rose. “Are you asking me to go up the river?”

“You would have a full contingent of guards,” he promised. She took a few shaky steps towards him. Arthur braced himself to catch her again.

“That would require me revealing myself to your men,” she pointed out.

“Not if you showed yourself like you are now,” he replied.

The mermaid crossed her arms. Arthur tried to ignore the effect it had on her chest.

“I can barely walk like this, and you want me to pretend to be human?” she asked.

“I…”

She wasn’t wrong.

“Could you mark the location on a map if I gave you one?” he finally asked.

Roshanara paused. She ran a hand through her hair, which shifted away from covering her breast. Arthur sucked in a breath.

“That requires me to go up the river, out of the sea,” she reminded him. “If I went as a human, I would likely die. If I go as myself, and I am caught, I can only do so much. I don’t have a weapon.”

A few more deep breaths. She was right. He barely knew her and he was asking her to risk her life for him so they could find the Institute. And though he knew his men could be trusted…

“Danse.”

She looked up at him. “Your Paladin?”

“He knows about you. I could send him to meet you at the mouth of the river. You keep to the deepest parts, maybe leave some kind of marker for him so he knows where you are and can keep an eye out for hostiles.” He found himself fidgeting, mission plans and mental maps filling his mind as he began to plot out the objectives. “If you need to, you can turn human and he can pretend he’s fished you out of the river.”

“Fished me out,” she repeated. Her brow furrowed.

“…did I cause some kind of offense?” he asked.

She waved her hand. “I do not like the concept of being _fished out_. It implies a capture that ends in death.”

“He will pretend to have rescued you,” Arthur assured her. “If need be, he can throw down some clothes for you to change into.”

She laughed. The sound warmed him, different to that hot flash of delighted fury from earlier.

“He may need help getting me dressed,” she admitted, smiling. “I’ve…never worn clothes in my life.”

A brief image flashed in Arthur’s mind of her human form wearing one of their flight suits, and him taking it _off_ her. He tried to keep his next breath level. He wasn’t certain he was successful.

“In any case,” his voice didn’t squeak the way he was afraid it would, “if you’re willing to lend us your aid, is there anything you’d ask in return?”

She let out a soft, embarrassed laugh, and looked away. “I…maybe. I don’t know.”

His brows raised. “Do you need time to think it over?”

She took a deep breath. The rise and fall of her chest was in his sight whether he looked or not and he felt his ears burn. He wondered what she was thinking about.

“I will help you,” she finally said, “but one of you is going to need to help me. My legs are strong but…I don’t know how to walk.”

Arthur remembered how easily she’d fallen on him and took a breath of his own. “I’m sure Danse will be in power armour, so he might carry you.”

“Swept off my feet by a handsome man in shining armour,” Roshanara chuckled. “Perhaps I won’t need that much of a reward after all.”

Disappointment sank in his stomach like a stone. He tried not to let it show on his face. “Alternatively…I can help you to walk.”

She nodded. “I don’t imagine it should take too long. My main problem is balance, not strength.”

“Then we should start now.”

Roshanara looked up at the moon. “Tomorrow. When it gets dark. You,” she smiled, “should sleep.”

It must have been well past midnight. He wasn’t sure how long he had been out here. “Tomorrow, then,” he agreed. He held out a hand.

There was no hesitation as she gripped it with her own, stumbling towards him. Arthur was ready for her as she fell into him. Could he carry her?

His hands found the backs of her knees and the mermaid _shrieked_. Arthur jumped, still holding her, his eyes wide open. A few moments passed and her loud panting was suddenly ringing in his ears.

“I’m sorry,” she gasped, gripping him tightly, “nobody warned me that the skin there was so _sensitive_.”

“I…”

Oh. Of course. It was unlikely that she’d ever had anyone touch her thigh. “I didn’t mean to,” he began.

Her finger pressed against his lips. “I know,” she murmured. Her body was still moving against his own and he gritted his teeth behind his lips. Her tongue swept out to wet her own. More heat filled him, both from her body and from his own. The press against his flight suit was almost unbearable. “…perhaps I know what I want as a reward.”

Arthur’s eyes widened.

The same voice from last night suddenly boomed across the water. Roshanara looked behind her. “Ah, there you go,” she began. “Help me back to the water?”

“What _is_ that?” Arthur asked, as he slid a hand around her waist. Her skin was unimaginably soft beneath his fingertips and it fluttered a little at his touch as he guided her back to the shore.

“How about I tell you tomorrow?” she replied with a laugh.

Arthur’s brow furrowed. “You can’t expect me to sleep after you said that.”

She looked at him, and as her feet touched the water, her eyes shimmered. “I’ve been ensuring your excellent sleeping habits for two nights now.”

She wasn’t wrong.

“Why the secrecy?”

Roshanara fell back into the water. As before, it bubbled and glowed. Her head emerged from the bubbles. “Because he wants to meet you, rather than have me tell you about him.”

_He????_


	4. Chapter 4

Arthur didn’t know what to expect tonight, as he watched the shoreline. His stomach fluttered, and he leaned against the wrecked plane, his eyes going to the dent in the metal every so often, remembering the way the mermaid had just. _Squeezed_ it.

And then she’d told him that there was another of her kind waiting to meet him. A merman.

A gentle sea breeze blew into his face and he took a deep breath. Well, it was almost midnight. What would happen if this other merperson disagreed with him, or didn’t like him? Would Roshanara be forced to stay in the ocean?

He swallowed.

The gentle wash of water on sand grew louder, and as Arthur watched, the waves suddenly grew, slapping viciously against the shore. He backed up a few feet. He needed something to cling to in case a larger wave crested, but-

A wall of water crashed against the rock that Roshanara usually sat on, and the sea flooded across the sand, submerging Arthur’s feet. He cursed, hopping against the plane, as it slowly receded.

“It’s just a bit of water.”

Arthur felt the air flee his lungs.

A broad figure was seated on the rock, very, _very_ different from the mermaid’s. Arthur switched on his lantern. Golden-orange scales reflected its light back at him, dazzling him briefly.

 _Golden-orange_.

“You’re the one who saved Knight Bristow,” Arthur whispered.

Silver eyes regarded him with a hint of amusement.

“Was that his name?” the merman asked, leaning forward. Long locks of black hair slid forward, not enough to cover his body, but Arthur wished it would. The man was as built as any Brotherhood soldier, and as Arthur slowly gave him a once over- twice over- with the light, he could see scars standing out on the dark skin. Like the mermaid, scales and hard fish skin decorated his body in various areas along his outer arms and shoulders.

All the fluttering in his stomach had gone, briefly, only to be replaced by another sensation – the warmth of arousal.

Arthur switched the lantern off and put it down. Meeting Roshanara had been so different. Something new, fantastical, exciting. She wasn’t intimidating.

This man…

Arthur wasn’t scared of _him_ so much as he was suddenly daunted by the thoughts he had running through his mind.

“What is it you want?” he finally asked. His voice cracked only a little.

The merman leaned back, and the moonlight gleamed off the water that still covered him. “It’s been two hundred years since Roshanara was so fascinated by something,” he began. “I just wanted to meet the man sating her… _curiosity_.”

There was a purr in the last word that made Arthur’s breath catch. He didn’t dislike it. “And?”

The merman chuckled. It made Arthur’s stomach swoop. A thick, muscular arm raised to lay across the golden lap. “I think she has good taste.”

It answered a question Arthur didn’t know he wanted answers to. He shifted. “And you are?”

The merman smiled. “Nautilus. Rosh’s mate.”

Arthur frowned. “Rosh?” _Mate?_

“Rosh. Roshanara. Are you worried I’m here to attack you for being competition?”

Arthur swallowed. He was picturing the merman tackling him, yes, but…for different reasons.

Nautilus’ brows rose. “Has she ever told you how wonderful you smell when your mind works like that?”

Arthur’s eyes widened and he took a few steps back. “You can smell me?” he asked faintly. Oh. _God_. “She never…”

“She’s polite,” Nautilus told him with a shrug. A smile, full of teeth, flashed in the moonlight. “Me, on the other hand. I find it _fascinating_. Most species, upon finding a new kind, have a habit of shunning, of running away or trying to destroy the newcomers. And some…”

Arthur took a deep breath just as the merman did.

“Well, some are rather more willing to _embrace_ it.” The golden tail flicked. “And I must say, I’m quite pleased to find that you’re one of the latter.”

“I’m not always so friendly,” Arthur said. “If you were the result of technology gone too far-”

Nautilus waved a hand dismissively. “I know what you think of synths. Which brings me to the other reason why I’m here.”

The merman looked away, and Arthur could barely hear a high-pitched clicking sound. There was a loud splash. Excitement burned in his gut, and when Roshanara climbed up onto the rock, he let out a heavy breath.

“Hello, Arthur,” she said, smiling at him. He quickly concentrated on the merman until she’d slipped her hair over her shoulders. He shouldn’t find it so embarrassing to see, but…

“Hello,” he replied. His voice came out breathless and his cheeks burned.

Nautilus laughed. “Have mercy on the poor boy, love.”

The mermaid looked at her mate with wide eyes, then gazed back at Arthur. “…oh.”

“As I was saying.” Nautilus looked back at Arthur. “You asked Rosh to help you find the Institute based on the smell in the water.”

Arthur swallowed.

“And you offered to help her learn to walk,” Nautilus added. “And whilst I’m perfectly aware that she’s capable of defending herself, I didn’t reach 410 years old without being wary.”

 _410 years old_. Arthur almost choked on his own spit, his eyes widening. Four centuries. _Four. Centuries_. If he thought Quinlan would have died happy meeting _Rosh_ , then Nautilus would have resurrected him.

“Wary?” he repeated weakly.

“Her human body has almost never seen use.” Nautilus ran a gentle hand through Rosh’s hair. “Even if you meant her no harm, I have no guarantee that something else wouldn’t. Even a few feet from the water as she is now, if something swooped down and stole her, she would be powerless. Despite all her strength.”

“What is it that you want?” Arthur asked.

“Nothing. Just to guard her,” Nautilus replied. “As I would guard anything I love.”

Arthur nodded, taking another deep breath. “I see.”

“Are you afraid of an audience, Arthur Maxson?” the merman chuckled.

The sound made his flight suit constrict around his crotch and Arthur couldn’t help the pictures in his mind. He forced them quickly down. “No,” he cleared his throat, “no, that won’t be a problem.” He quickly looked over at the mermaid. She was gazing at him with earnest eyes and a soft smile. “Whenever you’re ready.”

She slipped off the rock and back into the water. Arthur approached the shore, and held out his hand to help her up as she stood shakily. She didn’t fall on him this time. He didn’t know if he was disappointed or relieved. Perhaps a mixture of both.

He watched her briefly look him up and down, appraising how he stood, and she copied him, placing her hands on his shoulders. She wobbled a little as she did, but neither of them fell into the sand. She was _heavy_. All that muscle, like steel cord. It made his heart jump, thinking of how strong she was.

And by extension, how strong Nautilus must be.

No. He couldn’t get distracted. He had agreed to teach her how to walk, and he’d done so partly out of a selfish desire. And now this was the price he paid – having a temptation sitting lazily on the rocks nearby as he helped Rosh to keep her back straight and place her feet.

“How long have you been in command?” Nautilus suddenly asked.

“Four years,” Arthur replied. Rosh’s foot slipped and he quickly slid his arm beneath hers.

“You’re very young for that job,” Nautilus commented.

Arthur bristled. “I’m not a child.” He quickly gazed over at the merman. There was no mockery in his gaze. In fact, he looked far too serious.

“But you were _young_ ,” Nautilus emphasised. “Was there really no one else?”

Rosh’s hands moved to his biceps.

“I’ve been groomed for command since I was a Squire,” Arthur told him. He tried not to snap. “There _were_ no others.”

Nautilus nodded. “That,” he began, “is very unfortunate for you, then.”

Arthur frowned. “Meaning?”

“Meaning that your youth has been spent likely cleaning up the messes left by the less competent,” Nautilus began. “I’ve seen your soldiers trying their best to enjoy themselves, even in a time of war, and many of them are older than you. I don’t see that from you.”

Arthur stopped walking.

“Nate,” he heard Rosh say softly, warningly.

“I’m the Elder of the Brotherhood of Steel,” Arthur began. “I’m the last of the Maxsons. The blood of our founder flows through my veins. I _can’t_ have the same life as my soldiers. I can only lead them to the best future possible.”

Nautilus gazed at him. Arthur clenched his jaw. What was the merman thinking right now? He’d give anything to know. He heard Rosh sigh in his arms, sounding frustrated.

“Rosh,” Nautilus looked at the mermaid. Briefly, Arthur felt his heart plummet, and then the merman’s brows rose. “You have _very_ good taste in humans.”

Something in Arthur’s heart leapt. Had he passed some kind of test? Or gained some kind of approval?

“I had no intention of causing offense,” Nautilus began. “You’re young, even by human standards. Regardless of bloodline or expectations, or indeed even competence…” The merman looked him over. “There are things nobody should have to shoulder before their time.”

He felt Rosh’s hands on his forearms and looked back down at her. Her blue eyes were gleaming with curiosity, her lips slightly parted. Butterflies filled his stomach.

“I…”

“Are you going to question him all evening or can I learn how to walk?” Rosh drawled.

Nautilus laughed, and suddenly it was like whatever shroud had come over them was gone. Briefly, Arthur wondered if that was magic.

“You’re right,” Nautilus agreed. “I came here to make sure nothing hurt my love, and here I am, asking too many questions I don’t have reason to ask.”

“It’s a terrible habit of his,” Rosh murmured. “In most cases. Sometimes, it’s…useful.”

Arthur’s brow furrowed and he led her a few steps back. She seemed to have almost gotten the hang of it. “Useful?”

Her eyes darted away, and her lips disappeared briefly between her teeth. Nautilus’ soft laughter met Arthur’s ears.

“Again, you don’t reach 410 without learning to ask what works best,” Nautilus murmured.

Arthur closed his eyes briefly. His earlier irritation had died away, and once again, that heat was just about present. “I see.” He didn’t know what to do. He’d never been in this situation before.

Rosh sighed. “Don’t scare him,” she scolded her mate. “Look at him, he’s nervous.”

“If you like, I can take human form too,” Nautilus offered.

Arthur looked down, briefly, at where Rosh was hidden entirely by her hair, and realised that if Nautilus appeared the same way, there would be nothing to conceal him.

Those same questions about mer anatomy flashed up in his mind, only this time it wasn’t Rosh he was thinking of. His suit was uncomfortable now.

“Or perhaps not,” Nautilus conceded. Arthur shot him a glance and realised that the merman was staring straight at him. “You really do smell wonderful when you’re thinking about it.”

That wasn’t helping.

Arthur wasn’t uncomfortable. Not really. But his body was giving out signals and working in ways that he- he didn’t know if they should. He didn’t know these merfolk at all, not really. Acting on his desires…was it safe?

“Are you afraid of us?” Rosh asked softly. “I’m sorry. We were just so excited to meet you, and when you suggested helping in the fight against the Institute, and Nate wanted to meet you, I…”

“Do you want to sleep?” Nautilus asked.

Arthur paused. “I don’t know if I can.”

“I can help with that,” Rosh whispered. “I can help. I promise.”

“I’m teaching you,” Arthur pointed out.

“You can teach me tomorrow.” Rosh cupped his face. “And the next night. And the night after that. As long as it takes.”

A loud splash echoed across the water and Arthur turned to see that Nautilus was gone from the rock. It didn’t take him long to reappear, standing up on the shore. Arthur didn’t know where to look.

“I don’t need to smell you to sense your apprehension,” Nautilus told him. “Tell me your concerns.”

Arthur couldn’t fold his arms when Roshanara was in them, but he kept his eyes on Nautilus. “You asked some questions of me that I have not had to think about, ever. You’re both strangers, you even more so than she is. You keep mentioning how I smell; it’s…unnerving. You…both have openly stated an interest in me and it’s unusual.”

“How so?” Rosh asked.

 _Because most people want the Maxson name, and neither of you could care less about it_. “People are usually more concerned with my status,” he replied. “With what they can get from my favour.” He paused. “I can’t deny my…reactions…to your presence.” He gestured to the two of them. “This…is all wholly unprecedented. And selfish. Of me.”

“Because you enjoy spending time with a naked mermaid who has already straddled you,” Nautilus drawled.

Arthur’s cock throbbed.

“I’m sorry about that,” Rosh muttered.

Arthur swallowed. “I am not…I do not put myself in the hands of strangers, for good reason. I’m trying to be cautious.”

Nautilus nodded. “You’re worried about trusting us, after everything you’ve experienced in life. I see.” The merman took in a long breath, and then lapsed into silence.

“I won’t insult you with a lie,” Arthur told him firmly.

“I’m already in admiration of you, Arthur Maxson,” Nautilus said with a small laugh. “You don’t need to try and charm me any further.”

Arthur felt his cheeks burn. “That wasn’t my intention.”

Nautilus’ smile was disarming. “No, and that’s what makes it better.” He slipped behind his wife, his arm sliding around her waist. “Well then, in light of that confession, what would you like to do? Whilst I thoroughly enjoy flirting with you, I’m not intending to cause discomfort. And my questions come from curiosity, not accusation or malice.”

“I don’t,” Arthur struggled to find the words, “dislike the flirting. It’s just…unusual. For it to be earnest.”

Nautilus tutted. “Unfortunate.”

“Is there anything we can do to gain your trust?” Rosh asked softly.

“…you are already helping me,” Arthur finally said. “I just need time.”

She smiled up at him. “Time is a commodity we have plenty of.”

“May I ask you another question?” Nautilus inquired.

Arthur looked up. “Which is?”

“Do you happen to prefer one of us flirting? In your world, your society, do you find it odd that we both want you?”

Arthur bit his lip. “I don’t… _prefer_ …at least, not in that I want one of you more than the other,” he admitted. “Perhaps others find it odd. I…”

He exhaled heavily.

“…should sleep. I should rest. It’s late.”

“Will you be here tomorrow?” Rosh asked.

“Yes.” It slipped out faster than he wanted it to. “I will.”

Two beautiful smiles made his heart briefly stop.

“Then we’ll see you tomorrow night,” Rosh said. “Thank you for your lesson, Arthur.”

Nautilus picked her up without warning, and she _shrieked_ again, her arms wrapping around his neck. Arthur’s mouth went dry at the sight of them together. He knew he would likely fall asleep the moment he got back to his quarters, but if he could capture that sight in his mind, even for a little, he hoped he would be able to find some relief first.

“A pleasure to meet you, Arthur Maxson,” Nautilus told him. “And I look forward to seeing you tomorrow night. Don’t be late.”

He waded into the water, carrying his mate in his arms, and Arthur watched them both disappear below the surface. The water gleamed and bubbled again. Two heads popped up, and they waved to him. And then they were gone with a flick of their gleaming tails.

Arthur let out a groan.

 

* * *

 

 Arthur slept deeply. But vividly. His dreams were full of flashing scales and dark hands. He could almost feel their touch on his skin and it was pure torment. He kept thinking of Rosh’s softness against him and wondering how Nautilus – Nate – would feel if he touched him.

It was torture.

Whatever conflict his rational side had over trusting the merfolk, his body and his desires had no such problems. He remembered the way Rosh had shrieked when her legs were touched and it simply fed into his imagination.

The covers were on the floor when he awoke, aching, his skin burning. He was panting like he had just been doing drills, but he wasn’t tired. He felt refreshed. Awake. Alert.

Trying to concentrate all day was worse than trying to sleep peacefully. Now that the images had been clearly put in his mind, and the events played out in his imagination, he couldn’t think straight. Or at all.

By the time evening came, Arthur was almost a wreck. He had to steal a moment to himself to get some relief. Briefly, he worried that they had cast some sort of spell. They must have. He had never been this way before. He didn’t understand it. When midnight came, he was almost vibrating, waiting down on the beach to see who would show first. The waves rushed across the sand again, wetting his boots. The cold briefly shocked him out of his trance, but that relief vanished the moment he looked up and saw the familiar golden shape of the merman, lounging on the rocks like some sort of king.

“Good evening.”

That _voice_.

“Nautilus,” Arthur began. “Where is Roshanara?”

“She’ll be joining us briefly,” Nautilus assured him. “And please. Call me Nate.”

“Nate.” Arthur nodded.

“I was thinking about what you said last night,” Nate admitted. “About trusting us. Needing time.” He leaned forward. “And it occurred to me that perhaps you might have more time if you weren’t so concerned with this mission to locate the Institute.”

Arthur frowned. “Isn’t that why Roshanara is learning to walk?”

Nate nodded. “Except,” his gaze roved Arthur’s body, “there’s no reason why _she_ needs to be the one to find it when _I_ am perfectly capable too.”

“You’re going to help me find the Institute?” Arthur asked. His heart drummed in his chest as excitement filled him.

Nate laughed. The sound wasn’t mocking, just amused, and he finally looked back at Arthur, a grin gleaming in the moonlight.

“I’ve already found it,” Nate told him. “There’s a pipe in the river that will take you straight to them.”

Arthur’s eyes widened.


	5. Chapter 5

“I never realised there were two of them,” Danse muttered, fiddling with his whiskey. “Probably should’ve, when Roshanara didn’t turn out to be _orange_.”

“Mmm,” Arthur agreed.

The celebrations had died down not long after the merfolk left an hour ago. The rowdier soldiers were dancing in the old terminal, and Arthur was sitting on a bench under the sky with the Paladin, watching the water. His eyes were drawn to every flash of light on the waves, hoping to see the flick of a tail.

“Why do I feel like you’re not really here?” the Paladin chuckled

Arthur started, sitting up. “…I have no defense on that front,” he admitted.

“If I didn’t know better, I’d say you’re waiting,” Danse told him. “Anything in particular that you were wanting to spot?”

Arthur leaned back against the bench. “You disapprove?”

A soft laugh escaped the Paladin. “After everything they did to help us? I’m more worried that we’ll lose you to them completely.”

Arthur’s cheeks burned. “I’m not abandoning the Brotherhood,” he promised.

This time, Danse snorted. “I’ll hold you to that.”

Light flashed off the rock, and Arthur scrambled to his feet, just as Roshanara appeared, leaning against the outcrop. He wasted no time in heading towards her, and he could see Nate bobbing in the sea not far from where she was standing, looking a little wobbly.

She was smiling expectantly as he approached. He could hear Danse behind him, but for a moment, Rosh gave him her full attention. “Arthur,” and then she looked to his left, “hello, Danse.”

“Roshanara.”

“Were the celebrations not to your liking?” Arthur asked, gazing at the mermaid. Whatever clothes she’d worn earlier, they were gone now, and she was as bare as she’d been all the other times she’d taken this form. He swallowed.

She just laughed softly. “My mate and I…were hoping you’d join us.”

Arthur started. “Join you?”

She gestured with her head to the waters behind them that stretched out into the dark. “Yes. Not far. Just for a swim.”

He breathed in deeply. His stomach fluttered. “I don’t know if I could keep up.”

She tucked some hair behind her ear. “We’ll help.”

Arthur turned to look at Danse. The Paladin was looking at him with a _smirk_.

“What, you asking my permission?” Danse laughed. “You’re my superior. I’ll keep the Proctors off your back for a while. Don’t think I can cover if you aren’t in your bed by dawn, though.”

Heat rushed through Arthur’s body. “Thank you, Danse,” he breathed, and drew closer to the mermaid.

Her hand pressed against his chest. “You won’t be needing this,” she told him, tapping at the suit.

Arthur had never stripped quicker in his life. He left his boxers on, and as he moved to head back to the bench, clothes in hand, Danse simply took them from him.

“Fascinating,” he heard Rosh murmur behind him. “I’ve always wondered.”

Her eyes drank him in. He suddenly realised that there was an insistent hardness in his underwear, but Rosh simply tilted her head, an amused look briefly overtaking the pure wonder on her face.

“Does that stay on?” she asked. “Is it part of you?”

“What?” Arthur looked down at the white fabric still covering him. “No.”

“Hmm.” She looked up, grinning, and held out her hand. “Don’t worry about the cold. We won’t be in the water for long.”

“Wait.” Arthur stepped closer, and wrapped his arm around the back of her shoulders. “May I?”

Rosh nodded, brow furrowing, and Arthur finally picked her up with a loud grunt. _Fuck_. She was _heavy_. She giggled as he took a few steps forward, bare feet hitting the water. It lapped against his shins and he shivered.

“You won’t be able to do that for long,” she warned with a smile, but he just grunted, and waded further in.

“He’s going to kill himself,” Danse muttered, and Arthur turned to see him walking away towards the airport.

He could see Nate bobbing in the water ahead, and as he kept going, the cold suffused his knees, then his thighs. He gritted his teeth as it swallowed his hips.

“Hold on, Arthur,” Rosh said softly. “Let me down.”

He did so, and she slipped from his arms and into the water. It started to glow softly around her hips, a few little bubbles popping from the surface.

“I didn’t want your back to break under my full weight,” she said, and then her head slipped under, and the dancing lights and churning water started in earnest. Seconds later, her true form surfaced, long hair flowing around her like a fan. Her hands grabbed at his waist, pulling him a little deeper until she was able to float and keep their heads level. “I have a gift for you.”

He swallowed. “What kind?”

Rosh smiled, her eyes sparkling. “A very useful one.”

And then she leaned in and kissed him.

Arthur’s hand grabbed her waist, the other finding her cheek, and he groaned at the softness of her mouth as her tongue slipped past his lips, just briefly. All too soon, it was over, and Rosh pulled away. “There,” she whispered, “you’ll find breathing a little easier now.”

Arthur was finding breathing difficult _now_.

Rosh grasped his hand, and with a flick of her tail, his feet were off the sand, and they were floating together in the water. The cold seeped into his skin, and he was grateful for Rosh’s warm touch in his as they reached Nate.

“Ready?” the merman asked.

“For?”

Nate took his other hand. “Want to test your new breathing?”

Arthur’s eyes widened. His heart drummed against his ribcage, but after a few moments, he nodded. And with that, they disappeared below the surface.

The cold smacked him in the face when he descended, and out of instinct, his mouth opened. Bubbles of air escaped, but Arthur didn’t feel that familiar tightness of a held breath in his lungs. He kept his eyes closed, and even if he’d opened them, the night above would have kept the water pitch-black anyway. He let the merfolk pull him along, half-heartedly kicking out with his feet. The way the water rushed past him, they were going _fast_.

And he was _breathing._ Water slipped past his lips and air filled his mouth. He wished he could have seen the ocean around him.

Then they burst from the water, spraying sea salt as they emerged. Arthur blinked the sea from his eyes, and found himself facing an old tugboat bobbing in the waters. It was wreathed in lanterns, its deck facing away from the beach so that they wouldn’t be seen. Nate climbed up the side, and pulled Arthur with him. Rosh followed.

The deck was clean of any debris and muck, and Arthur could see what they’d done with their old clothes. They lay across an open section of deck as a makeshift cover.

Arthur turned to look at the merfolk, and watched, fascinated, as their scales dripped from their legs and became water that disappeared into the depths below. Rosh was still wobbling as she approached him, her eyes fixed on him. Her palms splayed across his chest, fingers curling into the wiry hairs that grew there. Her eyes flicked to Nate, who appeared at Arthur’s side. Now that he was closer, Arthur could see that there was a dusting of black and silver hairs covering Nate’s chest.

“This would be easier if you laid down,” she whispered.

The ocean cold had kept him soft during the swim, but as Rosh’s soft touches brushed over his chest, it didn’t linger enough to keep him from being excited, and he did as she suggested, laying on top of the clothes. They smelt like the salty tang of the coast, and Arthur wondered if that was the smell of their skin lingering in the fabric.

He didn’t have long to think about that. Rosh straddled his thighs, and Arthur finally let himself look down. His eyes found a patch of hair above her mound, just like a human’s, and his cock pressed against his boxers with a vengeance. He watched her look down, and a soft ‘huh’ escaped her. There was a long pause. He felt her eyes burning into him, and he finally lifted his head. Nate chose that moment to slip in behind him, his warm bulk at Arthur’s back.

“May I?” Rosh asked gently. Her fingers tugged at the elastic.

Arthur nodded. He lifted his hips and let her undress him. Those blue eyes were sweeping him the whole time, as though she couldn’t quite believe that he was real. Arthur knew how she was feeling. He was lying here on a boat with a merman at his back and a mermaid tossing his boxers aside, and he still wasn’t sure this wasn’t a dream.

The weight of her settling back on his thighs convinced him pretty quickly, though.

Rosh leaned in and kissed him again, cupping his face. Her hair brushed along his stomach as her lips pressed against his, and Arthur didn’t know where to put his hands. He just wanted to touch. He ran his palms up her waist, over her belly, but his touch halted just before they reached the curve of her breast, hidden beneath her hair still. Nate shifted behind him, and he felt Rosh’s hair brush against his hands. Arthur opened an eye to see that the thick dark waves had been moved aside, and Nate’s hand grasped his hip. As Arthur moved onto his side, pulling Rosh with him, Nate’s hips met his ass, and he felt a stiff heat pressing against him. He tensed.

Rosh nipped at his lip, her tongue swiping gently over the marks, as Nate’s mouth found his neck. Arthur felt all the tension drain out of him immediately, escaping him in a long groan when Nate began to gently run his hand up and down Arthur’s hip. It didn’t slip any further, just brushing gently against the elastic marks in his skin as Arthur finally moved his own hand up. His fingers touched the underside of Rosh’s breast, and she responded with a soft moan. He let his touch move a little further up. She was silky-soft, warm beneath his fingers, and her kisses were filled with gentle murmurs of pleasure as his fingertips found her nipple.

“Arthur,” Nate tapped his shoulder, “hold on a moment, love. Let him breathe.”

Rosh pulled away, and Arthur found himself caught by the look in her eyes. Wonder, joy, and lust all mixed together in the sky-blue, and he had to tear himself away to look at Nate.

“Mm?”

“Have you ever done this before?” Nate asked.

Arthur paused, and shook his head.

“Ah,” Nate hummed. Rosh made a noise of agreement.

Arthur’s stomach dropped for a few seconds.

“Lie on your back for us,” Nate ordered softly, sliding out from behind him. “We didn’t realise. But when you were so timid touching Rosh…”

“Are you going to stop?” Arthur asked hurriedly, turning over.

Nate shook his head as he and Rosh slipped either side of him, moving in a mirror image of each other. The need that rushed through him hard him hard in seconds, the cold all but gone as their hands moved to his stomach.

Nate was the first to kiss him this time, turning Arthur’s head to face him on the left as Rosh’s mouth gently moved to his neck. Her hands drifted across him, petting his arm and his outer thigh. Nate did the same, his fingers making little trails over Arthur’s leg and bicep. More heat filled him with every little caress, and when Nate’s teeth sunk into his lip, slow and firm, his cock twitched.

Feeling their hands so close to him was almost painful, and he tried to shift his hips and brush against their touch, but he heard two soft laughs as they moved a little further down and a little further up. Nate’s nails dragged against the skin just above his knee as Rosh tapped her fingertips against his waist. It wasn’t quite torture, but his cock was throbbing already as they continued, and when Rosh began to kiss her way across his shoulder, gently pressing her lips to his chest, Arthur moaned.

Her tongue flicked out against his nipple, and he started, his arm clamping around her waist. Rosh giggled, her body pressing against his, and the softness of her inner thigh brushed against his as she curled into him. Her teeth nipped playfully around his chest, and when she traced over his stomach, he wriggled, grunting into Nate’s kiss.

“Needy and impatient, both of you,” Nate teased, sighing. He gave Arthur’s mouth a few more kisses that made Arthur’s lips tingle pleasantly. “I think you two need to sate your curiosity.”

The merman drew back, and sat away from them leaning against the side of the boat. Arthur looked up, and realised his breathing was laboured. Rosh’s hand braced against his chest, and their eyes met.

“What about you?” Arthur asked, looking back at Nate.

Nate chuckled. “I’ve spent time _exploring_ your kind before, Arthur. Besides, it’s fun to watch when she’s inquisitive.”

“You’ll give him a terrible impression of me,” Rosh muttered, but when Arthur returned to her, she was already looking at him like she wanted to eat him. The need rushing through his body made itself known again, but he lay back to let her explore.

She traced every scar and scratch reverently, her fingers marking the deathclaw markings that had once torn up his chest, and had now mostly faded. He didn’t stay idle; as Rosh shifted, moving her attention down his body, Arthur did the same. His fingers brushed the back of her leg, and he watched her eyes close briefly, lips parting. Nate made an approving noise as Arthur did it again, his hand moving up her thigh before heading back down to stroke her calf. Her legs were soft, with short dark hairs that stood up beneath his fingers.

Arthur wriggled his fingertips against the backs of her knees, and Rosh shot up with a shriek. He couldn’t stop the grin that plastered his face as she straddled him, her narrowed eyes promising revenge, even as Arthur gasped. The soft, slick heat pressing against his erection was unmistakeable, and if Nate hadn’t grasped his hand and brushed his lips over it, Arthur’s palms would have clamped down on her waist like a vice.

“Rosh,” Arthur panted. There was a plea there somewhere. Whether that was for her to get off him or to sink down onto him-

Rosh rolled them both over with a few swings of her powerful hips, and Arthur had to ignore the urge to press himself against her slit and sink himself in. Instead he made sure her hair was out the way, and dropped his head to her breasts. After all the reading he’d done about this, he was ready to have some practical experience.

Nate had released his hand, and Arthur cupped the soft swells of flesh in his hands. He imagined he was clumsy, dropping kisses and licks against her dark skin wherever he pleased, but he could finally touch her, after the time he’d spent feeling and trying not to look. There was a hint of salt to her skin, and he felt her thighs draw up around his hips as her fingers tangled into his hair for a few moments. Then they were splaying across his back, tracing the muscle even as his tongue lapped at her nipple.

“I don’t suppose you want any instruction,” Nate murmured. Arthur looked up to see him grinning. Even in the half-light of the lamps, the thick, human-looking erection between the merman’s thighs was obvious. Something in Arthur’s mind wanted to get his mouth around it.

“Instruction?” he repeated. Rosh’s hips shifted against his, dragging herself against his erection, and he let out a wavering moan, waiting for a response from the merman.

“H-he doesn’t _need_ help,” Rosh panted. Nate laughed, nodding. Arthur returned his mouth to her nipple, sucking gently. Rosh cooed.

Part of him wished she was in her mermaid form. He wanted to know what her tail felt like if he touched it. But he settled for grinding into the heat between her thighs.

“Need a bit of relief, Arthur?” Nate asked.

Arthur grunted, and looked up again to see the merman had, somehow, moved closer without them realising. Those silver eyes were fixed on him, drinking in the sight of him, briefly looking down at the mermaid, and then Nate gave them an approving smile.

“Get on your back again, and I’ll show you,” Nate told him.

Slowly, Arthur slipped away from the mermaid, despite her noises of complaint, and rolled onto his back. Nate leaned back, and dragged a small satchel towards them, pulling out a small bottle.

Arthur gazed at it. “What’s that?”

Nate put the bottle to one side. “It’s oil, for if you want me, as well as her.”

Arthur blinked. He thought back to everything he’d read. Yes. Of course. _Of course_.

Nate gazed at him. “…you do know why, yes?”

“Yes,” Arthur said hurriedly.

Nate nodded. “But you’ve never…”

“No.” He watched the apprehension briefly flit across Nate’s face. “You’re not going to stop,” Arthur began, almost pleading.

Nate was silent for a few moments. Then he grinned at him. “No.”

Rosh curled up against his side again as Nate drew him in for a brief but deep kiss that left him panting. His teeth scraped against Arthur’s neck, and then his kisses were moving down, briefly touching his chest, then his stomach, and then-

Nate’s tongue swept up Arthur’s cock from root to tip, and Arthur bucked upwards with a yell.

The merman did it again, and Arthur’s lips parted, noises escaping him. Rosh’s mouth was at his neck, little kisses and nips sending pleasure straight down to where Nate was lapping at him, slowly and gently. Every lick of the merman’s tongue forced air from Arthur’s lungs, and he tossed his head back, a frantic hand grasping Nate’s hair, holding on tight for some sort of anchor. He could feel his fingers trembling as Nate’s licks sped up, and when Rosh’s nails scratched gently across his chest, he bucked again. Strong hands spread across his hips and pinned him down.

“Fuck,” Arthur groaned. A hot, wet mouth wrapped around his tip, and Arthur couldn’t breathe.

Arthur had taken care of his own needs before. He’d touched himself plenty of times, and the pleasure he’d felt then was nothing compared to now. Fire licked along his veins as Nate’s head dipped, more of Arthur’s cock filling his mouth until his lips reached the root of Arthur’s length. He couldn’t get enough air in.

Then Nate bobbed his head, and Arthur felt like he was about to rip out the hair in his grip.

Rosh was still peppering his skin with kisses, and as Nate kept up the unbearably pleasurable _up-down_ of his mouth, Arthur twisted his head to bury his face in her hair, trying to take in breaths deep enough to calm his racing heart.

It wasn’t going to work.

Nate had done this before. Arthur wondered, at 410 years old, just how many times – or he would have, if Nate hadn’t paused to suck on him repeatedly.

“Do you want him to draw it out?” Rosh breathed against his neck. “Or would you like him to stop teasing?”

Arthur didn’t know.

Nate’s lips moved up, drawing around the head, and Arthur couldn’t stop his hips from squirming when the merman’s tongue teased at the slit in his tip. Swearing repeatedly, he wrapped an arm around the mermaid, his nails digging into her flesh.

Rosh _giggled_ , still giving him those little kisses as Nate returned to bobbing his head again, faster this time. Trying to think when this ecstasy was rushing through him was impossible. The coastal scent of Roshanara’s skin filled his lungs. He could taste it on his tongue.

Nate’s right hand moved, and Arthur heard the _pop_ of a cork. He looked down, just in time for Nate to draw his lips back up and release Arthur’s cock entirely. Arthur himself strangled down a frustrated and disappointed growl that simply came out as a groan.

Nate’s eyes met his. “I will _not_ do this, unless you want me to.”

Arthur’s mind was half-insensate with lust, but he sucked in a few deep breaths, gazing at Nate. His brain wondered just how that would work, if it would work, wondered if it would hurt. The need coiling in his gut told him not to think too hard about it.

“Will it hurt?” he asked. Slurred. His voice came out half-formed.

Nate paused. “It might. But if it does, we will stop. Is that something you’re comfortable with?”

Arthur was already nodding. The word _please_ was hanging on his tongue and he was fighting to keep it down. Nate knelt back down.

“Remember,” he poured some of the bottle’s contents on his finger, “tell me if it hurts.”

The merman’s lips were soft on his cock as Arthur lay back, his breath coming out in shaky gasps as each kiss was followed up by a lick. He could feel the rough fingertip stroking at the ring of muscle, and he tried to keep himself relaxed and slack. It helped that Rosh draped herself over his chest, dropping gentle kisses against his mouth, and Nate’s mouth being out of sight made those little laps feel somehow more intense. Arthur’s gaze fixed on her instead, and as one hand curled into her hair, the insistent heat of his arousal seemed to make him bolder. He drew his fingers over her thigh, then down, dropping between her legs, before sweeping a path up. Rosh’s eyes fluttered shut, and as Nate pushed his slick finger slowly past the muscle, Arthur’s thumb pressed against the mermaid’s nub.

The effect was instant, for the both of them. Arthur groaned, and a shaky yelp escaped her mouth. He stroked his thumb in a circle, his legs tensing. Nate kissed his tip, tongue stroking along the ridge, and heat turned Arthur’s bones to water, allowing the merman to slip his finger a little deeper. Nate crooked that finger, and Arthur _swore_. Rosh nibbled on his lower lip, her hand dropping to his, coaxing his touch to be a little firmer and faster. Arthur did as he was bid, despite the shaking in his hands, and that was when Nate took the opportunity to close his lips around Arthur’s cock.

Arthur’s hand, formerly in Rosh’s hair, flew down to Nate’s instead, tangling into it as he shook. As Nate bobbed his head, his finger crooked and thrust, massaging gently across _something_ that made his skin prickle and sweat.

“Arthur,” Rosh moaned, and that didn’t help, her voice was laced with her magic as she parted her thighs wider and rocked her hips against his touch. He could _feel_ her arousal joining with his, and with every wave of pleasure that his touch drew from her, it washed back over him and dropped to where Nate’s mouth was sucking on him. It felt so good that it _hurt_.

His curses were muffled now and again by Rosh’s frantic kisses, and he sped his thumb up again as another finger stroked against the one buried in him, working the oil into his body. He tried to keep relaxed, but as the sucking stopped, the firm licks against the underside of his tip, down his shaft, began earnestly. He knew now what Rosh had meant earlier. Did he want Nate to stop teasing? He didn’t know. All he knew was that he couldn’t get enough of this.

His cock twitched. Arthur’s eyes widened. Half of him was surprised that he hadn’t reached his peak quicker, and the other half, as the pleasure rose, and rose, spurred on by another finger that slowly pushed into him, had been clawing at the walls, hoping for an orgasm, the moment that Nate’s touch had gotten anywhere near his cock.

Rosh was still gasping, her head buried in his chest, as Arthur arched, relief rushing through him, curling his toes and sapping his strength. His voice cracked halfway through crying out in pleasure, and his hand stilled, even as a shiver rushed through him from head to toe.

And then, _fuck,_ it was too much-

He pushed Nate’s head away, and the merman didn’t fight him, pulling his fingers out as he went. Rosh’s shifting had his whole body twitching in sudden, unexpected overstimulation, and she smiled, trailing her fingers across his chest and listening to him as he _whimpered_.

Arthur Maxson didn’t _whimper_.

Or he did, apparently, as the merman drew away, leaning over the edge of the tug to clean his fingers off. Arthur lay back, trying to recover, trying to persuade his mind to work again and stop shifting, so that the fabric would stop brushing against him. He was only mildly successful.

Nate came and sat with him, until Arthur could see without the sky blurring, and his skin stopped feeling like the slightest brush would set him off again.

“Better?” Nate murmured.

Arthur blinked, looking up, and finally nodded. “Yes,” he replied, his voice raspy. Nate reached into his bag and pulled out a can of fresh water. Arthur cracked it open without hesitation, and began to drink greedily.

“What would you like to do now?” Nate asked.

Arthur’s eyes found Rosh’s. She was breathing heavily, and he knew that he’d left her unsatisfied. He swallowed. “I want…to do something,” he told them.

Rosh sat up as he did, and she gasped as he leaned over, wrapping one still shaky arm around her back and guiding her down onto the deck. All the reading he’d done, he’d always been curious. Her hands gripped his shoulders as he kissed her, trailing his lips down her jaw, over her neck, following the swell of her breast with his lips until he was lapping at her nipple. Rosh moaned, and her stomach lifted as she panted for air. Arthur didn’t spend long where he was – he trailed his mouth down, over her stomach. His hands pushed her thighs open.

Rosh’s breathing stopped.

It was Arthur’s turn to make one of these merfolk breathless, as his thumbs parted her lower lips, exposing her to him. _Built like a human_ , he thought with relief. His tongue swiped up the length of her, and Rosh gave him one of those beautiful yelps. _Don’t know what I’d have done if she wasn’t_.

He had no basis for comparison. She tasted tart, a bit musky, with the tiniest hint of salt. Maybe that was natural, maybe it was due to her mermaid biology. Arthur didn’t care. He rather liked it.

Nate’s fingers tugged his thighs apart, and Arthur felt that heat rush back with a vengeance as he kept licking. Rosh’s fingers grabbed his hair. The sharp tugging sensation just encouraged his renewed arousal. And as Nate’s touch stroked over his soft cock, he felt himself throb again.

“One of the few things a human woman truly benefits from,” Nate commented. Arthur started as oil dribbled against his ass, but he pulled Rosh closer and sucked gently at her nub until her voice broke.

“W-which…is?” Rosh gasped, because Arthur couldn’t ask.

“What he’s doing right now,” Nate said. “Trying to do that in our normal bodies is more difficult.”

As Arthur licked her firmly, Rosh whimpered out something that sounded like agreement, but her thighs were pressing against Arthur’s ears now, and he couldn’t really hear her. That was fine. She wasn’t trying to make him stop, and Nate was pressing two fingers against him again, slowly preparing him as the mermaid shook beneath Arthur’s mouth.

He moved his head a little, letting his fingers push against her slit, and marvelled at the _sensation_ of her. She felt so _soft_. She was so wet that when he drew his hand back, there was a _noise_ that came from her. He slipped them back in. He didn’t know where to touch, or what felt best, but he kept it up, his hand moving slowly. Occasionally, he had to draw in breath, otherwise he would lose concentration, because Nate added another finger and kept doing to him what he was doing to Rosh.

Then suddenly the mermaid was almost _singing_ , and he could hear her above him, her voice rushing through him like a caress. He was so hard it _hurt_ now, and he could tell she was getting closer as he listened to every word that escaped her. He let his other hand trail up to cup her breast, thumbing the nipple, and her whole body rocked.

Her thighs parted widely, and Arthur could hear Nate saying his voice.

“Arthur,” a hand skimmed down his back, “would you like me to-”

Arthur pulled his head away, looked back at the merman, and nodded. “Yes,” he panted.

As he dropped his mouth back to Rosh’s slit, something wet and thick pressed against his ass. Nate’s legs brushed his as he knelt behind him, and Arthur thrust his fingers faster.

“You look like you’re about to explode,” Nate teased, and from the swearing that came out of Rosh’s mouth, it must have been aimed at her. Arthur could feel her legs trembling as she drew closer to her peak, and Nate paused. “How about we let her come first?”

Arthur ignored the angry throb of need from his cock, and did as the merman suggested. Everything he’d learned from her so far, he put it to work, until Rosh’s hands were almost tearing at his hair, and her voice filled the air with a scream that vibrated through Arthur’s body as a wave of unrelenting pleasure. Her hips trembled against his mouth. Arthur kept kissing and licking, sucking until she finally pushed him away.

In that moment, Nate grabbed his hips, and Arthur made himself relax as the merman slowly, _slowly_ , inched himself into Arthur’s ass.

A sound escaped Nate, in a language that Arthur didn’t know, and it sounded so much like a primal growl that it made him shiver.

“Are you all right?” Nate asked. The words sounded forced, strangled.

“Are… _you_?” Arthur panted.

Nate chuckled. “I will be.”

Arthur found himself rolling onto his side, leaning against Nate, and groaning as the merman rolled his hips, _slowly_. Rosh sat up, trembling, to watch. Nate’s hands were still on Arthur’s hips, and Arthur’s eyes fluttered shut as the gentle hip movements drew soft moans from him.

“Tell me when you want me to go faster,” Nate murmured.

Arthur swallowed down the voice in his head that wanted more _now_. He’d never done this before. Nate was right to take it slowly.

Then the merman started nibbling at his neck, and Arthur blurted out _faster_ before he even knew he’d said it. The gentle laugh he got in response buzzed against his skin. Nate pressed a few kisses where his teeth had been.

“Give yourself a moment to adjust,” he advised, sweeping one hand up Arthur’s side, his arm hooking beneath Arthur’s. “We’ve got all night.”

Arthur’s eyes closed as Nate pressed a few deep kisses against his back, his teeth leaving marks in the skin, and opened them when he heard movement. Rosh was already lying down in front of him, her thigh slinging over his, and Nate reached down, grabbing her leg to drag her closer. Arthur’s cock pushed against her belly.

“May I?” she whispered, leaning in for a kiss.

Arthur nodded.

Rosh reached down, taking him in hand, and as he moaned, she angled him against her slit. Nate moved for them all, pushing his own hips forward, dragging Rosh closer, and in moments, Arthur was buried in her. He grabbed her waist without thinking, strangled panting escaping his lips as Nate rocked a little faster. The feeling of her around his finger and around his cock was _very_ different. But the heat, the wetness, squeezing down on him was breathtaking, and he pulled her against him with a desperate moan.

“Copy what I’m doing,” Nate ordered gently. “With my hips.”

It was difficult to concentrate on what Nate was doing, but Arthur did his best, following the movements the merman made as much as he could. Rosh let out little gasps every time he did. One hand wrapped around his neck, drawing him in for a kiss, and the other grasped his shoulder. She moved with them both, working her hips against theirs. As Arthur pressed forward, so did she, and when he moved back, she drew away.

“You two are beautiful,” Nate panted, kissing Rosh’s hand before he nipped at Arthur’s neck. He was going to be a mess of bits and bruises by the morning, but as Rosh moaned into his kiss, he couldn’t find it in him to care. He could just put it down to bruises from the Institute. It might not make sense, but-

Rosh’s nails raked down his chest and Arthur started, returning her kiss aggressively. “Nate,” he groaned.

“Mmm?” the merman grunted.

“More.”

 _Please_.

It went unsaid, but all he heard was a chuckle from behind him. Nate kissed his newest bite mark, and then he was giving Arthur _more_ , harder and faster, angling his hips a little. Arthur clutched Rosh tightly, pulling her flush against him. His kisses were sloppy but she didn’t seem to care, her soft thigh hooking over his hip. He felt her leg tense, and his hand dropped to follow it. She was pressing her heel into Nate’s ass, trying to coax him to go faster.

“Insatiable,” Nate panted. “Truly. You- _barely_ \- finished tasting her…and she wants _more_.”

Rosh’s lips found Arthur’s neck, and they were _sharp_.

The unexpected hint of danger, Arthur found, was an aphrodisiac.

He reached down and grabbed Rosh’s ass. She was _heavy_ , but that was fine. He was just anchoring her, using her own body as leverage to drive himself deeper. Nate laughed breathlessly behind him, peppering Arthur’s back with bites and kisses.

“You’re­, _mm_ , a fast learner,” he panted, reaching down to squeeze a handful of Arthur’s ass. Arthur rocked back against the touch, and Nate swore.

 _Oh_.

Arthur’s other hand, his right hand, raised to his mouth. He licked his thumb. Then he dropped his hand between Rosh’s thighs, and her nails almost drew blood when he began to rub at her clit in firm, fast circles.

“Nate!” Rosh yelped. Her eyes rolled up. “Nate, he’s…fuck _, Nate_ …”

“Fast learner,” Nate gasped, but this time he sounded admiring, less teasing, and the merman pressed another kiss against him, on the back of his head, before he gave him a few more bites along his shoulders.

Arthur wasn’t going to last much longer with that kind of treatment. Two voices in his ears, nips and licks and scratches all over his body, an excited mermaid wrapped around his cock and an enthusiastic merman behind him – he was surprised he hadn’t spilled already.

His stamina wasn’t going to last him long. He could already feel the tension in his body coming tight between this thighs, but if Rosh could-

 _“Arthur,”_ she groaned.

Nate’s hips moved faster. His cock was rubbing against something now, something that he’d only briefly brushed, and the pleasure that rocked through his body was almost paralysing. He barely recovered from the first blast of ecstasy when the next hit him, and then the next. He wasn’t coming, not yet, but he was _about_ to, and he managed to remember Rosh’s pleasure through his own, moving his thumb faster and harder.

Her voice broke. She scratched him again, and he was pretty sure, with the sting of the wind, that she might have broken the skin, but that wasn’t important. Rosh was almost shaking in his arms.

And then he felt her start to _squeeze_.

There had been a lot of research done on Arthur’s end before, and not just in terms of his choice of novels. Scientific research. He’d been given the proper talk about the human body by Quinlan and Rothchild when he turned 13, and later, before ever being Elder, he’d asked a few questions of the other Knights. Then, when he’d become Elder, and that information wasn’t something he could just _ask_ for, he’d turned to science books. And there had been enough on the subject for Arthur to _wonder_.

Orgasms were muscle contractions, he _knew_ that, and yet, it had never occurred to him just what that would _feel_ like if his female participant came with him _inside_ her.

Well, now he knew.

The clench and release of her inner walls tore strangled noises of pleasure from his throat, something swiftly drowned out by Rosh’s voice as she came again. Her magic let loose once more, blasting through him. Arthur felt himself unravel without warning, filling her. He tried to pull away and she clamped down on him with an iron grip, keeping him seated in her until he finally stopped _twitching_. It took longer than he expected.

Rosh pulled him in for another kiss, despite their breathlessness, and that was when he felt _Nate_ twitching.

 _“Arthur,”_ Nate groaned, his nails biting into Arthur’s hip. The oversensitive rub against that part of him was almost uncomfortable, but Arthur gritted his teeth, and rocked back into Nate’s lap. The merman’s teeth met Arthur’s shoulder, just briefly, sharp enough to prick him, and then he tore his face away and pressed his forehead into the short hairs at the back of Arthur’s head.

Nate came with sharp, panting cries that fanned over Arthur’s skin and cooled the sweat that had beaded there. He’d barely noticed it in the heat of the moment – several moments – but now it was obvious. He clutched him tightly until his orgasm finally abated, and then he slumped against the deck with a groan.

Roshanara was half asleep, but made no move to pull him out of her. Her hands were gently petting him, running through his hair and across his arms. Nate’s lips pressed against some of the bite marks.

“I hope that satisfied you,” he murmured, kissing his neck. “It certainly did for me.”

Arthur didn’t want to move, and he just let out a tired grunt, shutting his eyes.

“I think we wore out the human, my love,” Nate teased.

Rosh laughed gently. “Are you all right, Arthur?”

“Mmm,” he mumbled. “Yes. That was…”

Mindblowing. Unparalleled.

“Everything.”

Nate grasped his hand, and leaned over to press a kiss to Arthur’s knuckles. Arthur turned his head, and Nate caught his mouth, licking at his lower lip.

“So.” He kissed Arthur’s shoulder. “The Institute has been vanquished. Do we have your full attention, at least for a little while?”

Arthur blinked. “As much as I can spare. I…have plenty of jobs to oversee in the Commonwealth.”

Rosh kissed his jaw. “What will happen after that?”

“I’ll return to the Capital Wasteland,” he replied. “Why?”

Both of them hummed.

“I’ve never travelled much,” Rosh said. “It might be nice to see more of the world.”

Arthur’s stomach filled with butterflies. “Are you…offering to come with me?”

“Purely by sea, of course,” Nate added. “Do you live near the water?”

“Yes.” Arthur swallowed. “But at some point, I will need to marry.”

Rosh traced his shoulders as Nate nudged his neck with his lips.

“That’s expected,” Nate said softly. “But perhaps, after you’re done…”

“Done?” Arthur asked, frowning. “Done, in what sense?”

“Ruling. Commanding,” Rosh told him. “If you ever grow tired of your role, we will be there.”

His stomach was bubbling with emotion. His life was the Brotherhood. He would live and die by it. What they were suggesting…

“I may not live long enough to do that,” he admitted softly.

Rosh drew him in for a kiss. “Then don’t stray too far from the water, Arthur Maxson,” she murmured. “Because if you fall, we may be able to save you.”

His eyes widened. “How?”

Nate’s arms wrapped around him. “Making you one of us,” the merman said. “Sharing our blood. Could you see yourself doing that?”

Arthur paused. He didn’t know. Would it mean giving up the Brotherhood? It had suffered so many weak leaders in its past. He couldn’t just abandon it.

“Maybe,” he finally murmured. Rosh smiled. Nate settled down behind him. Arthur felt his eyelids droop, and he let himself sleep.


End file.
